Method for generating or recovering materials through smoldering combustion

Abstract

Methods are provided for generating or recovering gaseous materials such as hydrogen and solids such as metals through the smoldering combustion of an organic material. The methods include admixing a porous matrix material with an organic material, and, in some embodiments a catalyst, to produce a porous mixture. The mixture is exposed to an oxidant, initiating a self-sustaining smoldering combustion of the mixture, and collecting the vapors and combustion products or processing the porous matrix following combustion to physically separate the porous matrix material from ash containing inorganic materials of value. Additional embodiments aggregate the organic material or catalyst or porous matrix material or mixture thereof in an impoundment such as a reaction vessel, lagoon or matrix pile. Further embodiments utilize at least one heater to initiate combustion and at least one air supply port to supply oxidant to initiate and maintain combustion.

What is claimed is: 
     
       1. A method for producing and collecting a gas through smoldering combustion of an organic material, the method comprising:
 forming a porous mixture comprising the organic material and an added catalyst for the production of the gas; 
 heating at least a portion of the mixture; 
 forcing an oxidant through the mixture so as to initiate a self-sustaining smoldering combustion of the mixture and to cause the production of the gas, the catalyst accelerating the production of the gas and not being itself consumed during the production of the gas; and 
 collecting the gas. 
 
     
     
       2. The method of  claim 1 , where the organic material is selected from the group consisting of a liquid, a slurry, a semi-solid, a solid, and mixtures thereof. 
     
     
       3. The method of  claim 1 , where the porous mixture further comprises a porous matrix. 
     
     
       4. The method of  claim 1 , where the gas is hydrogen. 
     
     
       5. The method of  claim 1 , further comprising causing propagation of the combustion away from a point of initiation of the smoldering combustion. 
     
     
       6. The method of  claim 1 , where the components of the porous mixture are aggregated in one of a reaction vessel, a pile, or a ground-level cavity. 
     
     
       7. The method of  claim 1 , further comprising continuously feeding at least one of the components of the porous mixture into a zone of smoldering combustion. 
     
     
       8. The method of  claim 1 , wherein forming the mixture comprises batch-feeding at least one of the components of the porous mixture into a vessel. 
     
     
       9. The method of  claim 1 , wherein the catalyst accelerates the production of the gas by reacting with volatile organic gases formed by combustion of the organic material. 
     
     
       10. A method for producing and collecting a gas through smoldering combustion of an organic material, the method comprising:
 forming a porous mixture comprising the organic material and an added catalyst precursor; 
 heating at least a portion of the mixture; 
 forcing an oxidant through the mixture so as to initiate a self-sustaining smoldering combustion of the mixture and to cause the production of the gas; and 
 collecting the gas; 
 wherein the catalyst precursor is converted to a catalyst for the production of the gas by the heat from the smoldering combustion, 
 wherein the catalyst accelerates the production of the gas, and is not itself consumed during the production of the gas. 
 
     
     
       11. The method of  claim 10 , where the organic material is selected from the group consisting of a liquid, a slurry, a semi-solid, a solid, and mixtures thereof. 
     
     
       12. The method of  claim 10 , where the porous mixture further comprises a porous matrix. 
     
     
       13. The method of  claim 10 , where the gas is hydrogen. 
     
     
       14. The method of  claim 10 , further comprising causing propagation of the combustion away from a point of initiation of the smoldering combustion. 
     
     
       15. The method of  claim 10 , wherein the catalyst accelerates the production of the gas by reacting with volatile organic gases formed by combustion of the organic material.